Semiconductor light-emitting device and method of manufacturing the same

ABSTRACT

A semiconductor light-emitting device, and a method of manufacturing the same. The semiconductor light-emitting device includes a first electrode layer, an insulating layer, a second electrode layer, a second semiconductor layer, an active layer, and a first semiconductor layer that are sequentially stacked on a substrate, a first contact that passes through the substrate to be electrically connected to the first electrode layer, and a second contact that passes through the substrate, the first electrode layer, and the insulating layer to communicate with the second electrode layer. The first electrode layer is electrically connected to the first semiconductor layer by filling a contact hole that passes through the second electrode layer, the second semiconductor layer, and the active layer, and the insulating layer surrounds an inner circumferential surface of the contact hole to insulate the first electrode layer from the second electrode layer.

CROSS-REFERENCE TO RELATED APPLICATIONS

This is a Continuation of U.S. patent application Ser. No. 14/736,217filed on Jun. 10, 2015, which is a Divisional of U.S. patent applicationSer. No. 14/594,020 filed on Jan. 9, 2015, now U.S. Pat. No. 9,099,631,which is a Divisional of U.S. patent application Ser. No. 14/483,036filed on Sep. 10, 2014, now U.S. Pat. No. 8,975,655, which is aDivisional of U.S. patent application Ser. No. 13/179,325, filed on Jul.8, 2011, now U.S. Pat. No. 8,872,205, which claims priority of KoreanPatent Application Nos. 10-2010-0065967 filed on Jul. 8, 2010,10-2010-0075670 filed on Aug. 5, 2010, and 10-2010-0079225 filed on Aug.17, 2010, the disclosures of which are incorporated herein in itsentirety by reference.

BACKGROUND

1. Field

The present disclosure relates to light-emitting devices in which anelectrode for supplying current to a semiconductor layer light-emittingdevice is formed on lower surface of a substrate, and methods ofmanufacturing the light-emitting devices.

2. Description of the Related Art

In general, a light-emitting device such as a light-emitting diode (LED)has a junction structure between a p-type semiconductor and an n-typesemiconductor. Such a light-emitting device may be classified into ahorizontal light-emitting device and a vertical light-emitting deviceaccording to a position of an electrode connected to a semiconductorlayer.

Since a horizontal light-emitting device forms an electrode by removinga part of a light-emitting area, luminous efficiency may be reduced.Also, since a horizontal light-emitting device requires wire bonding, awire may be short-circuited due to heat generated in the horizontallight-emitting device.

In general, in a semiconductor light-emitting device, a conductivesubstrate is disposed under a semiconductor layer, an electrode isdisposed on another semiconductor layer, and wire bonding is performed.Since the electrode has a size large enough for current spreading, lightextraction may be limited. Since light is absorbed by the electrode,luminous efficiency may be reduced. Also, wire bonding for supplyingcurrent to the electrode is required.

SUMMARY

Provided are semiconductor light-emitting devices that may prevent alight-emitting area from being reduced by disposing a p-type electrodeand an n-type electrode under a semiconductor structure and may bepackaged without wire bonding, and methods of manufacturing thesemiconductor light-emitting devices.

Additional aspects will be set forth in part in the description whichfollows and, in part, will be apparent from the description, or may belearned by practice of the presented embodiments.

According to an aspect of the present invention, a semiconductorlight-emitting device includes: a first electrode layer, an insulatinglayer, a second electrode layer, a second semiconductor layer, an activelayer, and a first semiconductor layer that are sequentially stacked ona substrate; and a first contact that passes through the substrate to beelectrically connected to the first electrode layer, and a secondcontact that passes through the substrate, the first electrode layer,and the insulating layer to communicate with the second electrode layer,wherein the first electrode layer is filled in a contact hole thatpasses through the second electrode layer, the second semiconductorlayer, and the active layer to be electrically connected to the firstsemiconductor layer, wherein the insulating layer disposes on an innercircumferential surface of the contact hole to insulate the firstelectrode layer from the second electrode layer.

The contact hole may includes a plurality of contact holes, and each ofthe plurality of the contact holes may be filled with the firstelectrode layer.

An insulating layer may be formed on an outer circumferential surface ofthe second contact to insulate at least the second contact and the firstelectrode layer.

The second electrode layer may be a reflective layer that reflects lightgenerated by the active layer.

The second electrode layer may be formed of at least one materialselected from the group consisting of silver (Ag), aluminum (Al),platinum (Pt), nickel (Ni), palladium (Pd), titanium (Ti), gold (Au),iridium (Ir), tungsten (W), stannum (Sn), an oxide thereof, and amixture thereof.

The substrate may be formed of any one material selected from the groupconsisting of alumina, aluminum nitride, sapphire, and polymer.

The substrate may be a conductive substrate, and an insulating layer maybe formed on inner circumferential surfaces of through-holes in whichthe first contact and the second contact are formed and on a surface ofthe substrate.

The substrate may include any one selected from the group consisting ofsilicon (Si), germanium (Ge), and Si containing aluminum (Al).

According to another aspect of the present invention, a semiconductorlight-emitting device includes: a first electrode layer, a firstinsulating layer, a second electrode layer, a second semiconductorlayer, an active layer, and a first semiconductor layer that aresequentially stacked on a substrate; a first electrode pad that isformed on a portion of the first electrode layer; a second insulatinglayer that is formed on a remaining portion of the first electrodelayer; a second electrode pad that is formed on the second electrodelayer to extend toward the second insulating layer; and a first contactthat passes through the substrate to be electrically connected to thefirst electrode pad, and a second contact that passes through thesubstrate to be electrically connected to the second electrode layer,wherein the first electrode layer is filled in a contact hole thatpasses through the second electrode layer, the second semiconductorlayer, and the active layer to be electrically connected to the firstsemiconductor layer, and the first insulating layer disposes on an innercircumferential surface of the contact hole to insulate the firstelectrode layer from the second electrode layer.

According to another aspect of the present invention, a method ofmanufacturing a semiconductor light-emitting device includes:sequentially forming a first semiconductor layer, an active layer, and asecond semiconductor layer on a first substrate; forming a contact holethrough which the first semiconductor layer is exposed from the secondsemiconductor layer, and forming a contact layer in the contact hole tobe connected to the first semiconductor layer; forming a secondelectrode layer on the second semiconductor layer to surround thecontact hole; forming a first insulating layer on the second electrodelayer; forming a first electrode layer on the first insulating layer tobe connected to the contact layer; adhering a second substrate to thefirst electrode layer and removing the first substrate; forming a firstthrough-hole that is connected to the first electrode layer and a secondthrough-hoe that is connected to the second electrode layer from anexposed surface of the second substrate; and forming a first contact anda second contact that are respectively connected to the first electrodelayer and the second electrode layer by filling the first through-holeand the second through-hole with metals.

The forming of the contact hole may further include: forming a secondinsulating layer that covers the contact hole; and exposing the firstsemiconductor layer by etching a portion of the second insulating layerformed on a bottom of the contact hole, and the forming of the contactlayer includes forming the contact layer on the exposed firstsemiconductor layer.

The forming of the contact hole and the contact layer may includeforming a plurality of contact holes and a plurality of contact layers.

The forming of the second electrode layer may include: forming a thirdinsulating layer on the second semiconductor layer; exposing the secondsemiconductor layer by removing the third insulating layer thatsurrounds the contact hole; and forming the second electrode layer onthe exposed second semiconductor layer.

The forming of the first electrode layer may include: etching the firstinsulating layer to expose the contact layer; and forming the firstelectrode layer to cover the exposed contact layer.

The forming of the second through-hole may further include forming afourth insulating layer on an inner circumferential surface of thesecond through-hole.

According to another aspect of the present invention, a method ofmanufacturing a semiconductor light-emitting device includes:sequentially stacking a first semiconductor layer, an active layer, anda second semiconductor layer on a first substrate; forming a contacthole through which the first semiconductor layer is exposed from thesecond semiconductor layer, and forming a contact layer in the contacthole to be connected to the first semiconductor layer; forming a secondelectrode layer on the second semiconductor layer to surround thecontact hole; forming a first insulating layer on the second electrodelayer; forming a first electrode layer on the first insulating layer tobe connected to the contact layer; forming a first through-hole in asecond substrate to be connected to the first electrode layer, and asecond through-hole in the second substrate to be connected to thesecond electrode layer; forming a first contact and a second contactthat are respectively connected to the first electrode layer and thesecond electrode layer by filling the first through-hole and the secondthrough-hole with metals; and forming a third contact that is connectedto the second electrode layer from an exposed surface of the firstelectrode layer and is insulated from the first electrode layer;adhering the second substrate to the first electrode layer such that thethird contact contacts the second contact; and removing the firstsubstrate.

According to another aspect of the present invention, a method ofmanufacturing a semiconductor light-emitting device includes:sequentially forming a first semiconductor layer, an active layer, asecond semiconductor layer, and a second electrode layer on a firstsubstrate; forming a contact hole through which the first semiconductorlayer is exposed from the second electrode layer; forming a firstinsulating layer on the second electrode layer to cover an innercircumferential surface of the contact hole; exposing the firstsemiconductor layer by etching a bottom of the contact hole; forming afirst electrode layer on the first insulating layer to contact theexposed first semiconductor layer; adhering a second substrate to thefirst electrode layer and removing the first substrate; forming a firstthrough-hole connected to the first electrode layer and a secondthrough-hole connected to the second electrode layer from an exposedsurface of the second substrate; and forming a first contact and asecond contact respectively connected to the first electrode layer andthe second electrode layer by filling the first through-hole and thesecond through-hole with metals.

According to another aspect of the present invention, a method ofmanufacturing a semiconductor light-emitting device includes:sequentially forming a first semiconductor layer, an active layer, and asecond semiconductor layer on a first substrate; forming a contact holethrough which the first semiconductor layer is exposed from the secondsemiconductor layer, and forming a contact layer in the contact hole tobe connected to the first semiconductor layer; forming a secondelectrode layer on the second semiconductor layer to surround thecontact hole; forming a first insulating layer on the second electrodelayer; forming a first electrode layer on the first insulating layer tobe connected to the contact layer in a second region other than a firstregion of the second electrode layer; forming a second insulating layerto cover the first electrode layer; forming a second electrode padconnected to the second electrode layer in the first region on thesecond insulating layer; forming a first electrode pad in the secondregion to be spaced apart from the second electrode pad and to beconnected to the first electrode layer; forming a first contact and asecond contact in a second substrate by filling through-holes spacedapart from each other in the second substrate with metals; and adheringthe second substrate to the first contact and the second contact suchthat the first electrode pad and the second electrode pad arerespectively connected to the first contact and the second contact.

According to another aspect of the present invention, a method ofmanufacturing a semiconductor light-emitting device includes:sequentially forming a first semiconductor layer, an active layer, asecond semiconductor layer, and a second electrode layer on a firstsubstrate; forming a contact hole through which the first semiconductorlayer is exposed from the second electrode layer; forming a firstinsulating layer on the second electrode layer to cover an innercircumferential surface of the contact hole; exposing the firstsemiconductor layer by etching a portion of the first insulating layerformed on a bottom of the contact hole; forming a first electrode layeron the first insulating layer to be connected to the contact layer in asecond region other than a first region of the second electrode layer;forming a second insulating layer to cover the first electrode layer;forming a second electrode pad connected to the second electrode layerin the first region on the second insulating layer; forming a firstelectrode pad in the second region to be spaced apart from the secondelectrode pad and to be connected to the first electrode layer; forminga first contact and a second contact in a second substrate by fillingthrough-holes spaced apart from each other in the second substrate withmetals; and adhering the second substrate to the first contact and thesecond contact such that the first contact and the second contact arerespectively connected to the first electrode pad and the secondelectrode pad.

According to another aspect of the present invention, a semiconductorlight-emitting device includes: a semiconductor structure that includesa first semiconductor layer, an active layer, and a second semiconductorlayer; a first electrode layer and a second electrode layer that aredisposed on the second semiconductor layer and are respectivelyelectrically connected to the first semiconductor layer and the secondsemiconductor layer; an insulating layer that is formed on a top surfaceof the semiconductor structure to insulate the first electrode layer andthe second electrode layer; a plating electrode layer that includes afirst electrode pad disposed on the first electrode layer and a secondelectrode pad disposed on the second electrode layer; and an insulatingbarrier that is disposed between the first electrode pad and the secondelectrode pad.

The first electrode layer may cover a top of at least one contact holeto be electrically connected to the first semiconductor layer throughthe at least one contact hole that is formed from the secondsemiconductor layer to the first semiconductor layer.

The insulating layer may extend to be formed on a side wall of the atleast one contact hole so that the first electrode layer is insulatedfrom the second semiconductor layer.

The semiconductor structure may be obtained by removing a predeterminedsubstrate from a gallium nitride-based light-emitting diode stacked onthe predetermined substrate.

According to another aspect of the present invention, a semiconductorlight-emitting device includes: a semiconductor structure that includesa first semiconductor layer, an active layer, and a second semiconductorlayer; a first electrode layer and a second electrode layer that aredisposed on the second semiconductor layer and are respectivelyconnected to the first semiconductor layer and the second semiconductorlayer; a first insulating layer that is formed on a top surface of thesemiconductor structure and insulates the first electrode layer and thesecond electrode layer; a second insulating layer that covers the firstinsulating layer, the first electrode layer, and the second electrodelayer and exposes a first region where the second electrode layer islocated and a second region where the first electrode layer is located;a first metal layer that is connected to the first electrode layer inthe second region; a second metal layer that is connected to the firstelectrode layer in the first region; a plating electrode layer thatincludes a first electrode pad that is disposed on the first metal layerand a second electrode pad that is disposed on the second metal layer;and an insulating barrier that is disposed between the first electrodepad and the second electrode pad.

According to another aspect of the present invention, a method ofmanufacturing a semiconductor light-emitting device includes: forming asemiconductor structure by stacking a first semiconductor layer, anactive layer, and a second semiconductor layer on a substrate; forming afirst electrode layer and a second electrode layer on a top surface ofthe semiconductor structure to be respectively electrically connected tothe first semiconductor layer and the second semiconductor layer;coating an insulating layer that exposes a part of a region where thefirst electrode layer is located and a part of a region where the secondelectrode layer is located; forming a first electrode pad and a secondelectrode pad by plating a first electrode region through which thefirst electrode layer is exposed and a second electrode region throughwhich the second electrode layer is exposed; forming an insulatingbarrier by filling an insulating material in a boundary region betweenthe first electrode and the second electrode pad; and removing thesubstrate.

The forming of the first electrode layer and the second electrode layermay include: forming at least one contact hole from the secondsemiconductor layer to the first semiconductor layer; forming apassivation layer on the second semiconductor layer and the at least onecontact hole; exposing a portion of the first semiconductor layer byremoving a portion of the passivation layer located on a bottom of theat least one contact hole; forming a first electrode layer on theexposed portion of the first semiconductor layer; removing a portion ofthe passivation layer other than a portion that surrounds the firstelectrode layer on the second semiconductor layer; and forming a secondelectrode layer on an exposed area by the removing the portion of thepassivation layer.

The coating of the insulating layer may include: coating an insulatinglayer on entire top surfaces of the first electrode layer, the secondelectrode layer, and the semiconductor structure; and removing a portionof the insulating layer where the first electrode layer and the secondelectrode layer are located.

The forming of the first electrode pad and the second electrode pad mayinclude: forming a photoresist in a boundary region between the firstelectrode region and the second electrode region; forming the firstelectrode pad and the second electrode pad by performing plating withthe photoresist therebetween; and removing the photoresist.

The forming of the first electrode pad and the second electrode pad mayfurther include forming a seed layer on the first electrode region andthe second electrode region for performing the plating.

The method may further include planarizing top surfaces of the firstelectrode, the second electrode, and the insulating barrier.

According to another aspect of the present invention, a method ofmanufacturing a semiconductor light-emitting device includes: forming asemiconductor structure by stacking a first semiconductor layer, anactive layer, and a second semiconductor layer on a substrate; forming afirst electrode layer and a second electrode layer on a top surface ofthe semiconductor structure to be respectively electrically connected tothe first semiconductor layer and the second semiconductor layer;forming a first insulating layer that exposes a part of a region wherethe first electrode layer is located and a part of a region where thesecond electrode layer is located; forming a second insulating layerthat covers the first insulating layer, the first electrode layer, andthe second electrode layer; exposing a first region where the firstelectrode layer is located and a second region where the secondelectrode layer is located by etching the second insulating layer;respectively forming a first metal layer and a second metal layer in thefirst region and the second region; respectively forming a firstelectrode pad and a second electrode pad by plating the first metallayer and the second metal layer; forming an insulating barrier byfilling an insulating material in a boundary region between the firstelectrode pad and the second electrode pad; and removing the substrate.

BRIEF DESCRIPTION OF THE DRAWINGS

These and/or other aspects will become apparent and more readilyappreciated from the following description of the embodiments, taken inconjunction with the accompanying drawings of which:

FIG. 1A is a cross-sectional view illustrating a semiconductorlight-emitting device according to an embodiment of the presentinvention;

FIG. 1B is a cross-sectional view illustrating a modified example of thesemiconductor light-emitting device of FIG. 1;

FIG. 2 is a cross-sectional view taken along line II-II′ of FIG. 1A;

FIGS. 3A through 3J are cross-sectional views for explaining a method ofmanufacturing a semiconductor light-emitting device, according to anembodiment of the present invention;

FIGS. 4A through 4C are cross-sectional views for explaining a method ofmanufacturing a semiconductor light-emitting device, according toanother embodiment of the present invention;

FIG. 5 is a cross-sectional view illustrating a semiconductorlight-emitting device according to another embodiment of the presentinvention;

FIGS. 6A through 6G are views for explaining a method of manufacturing asemiconductor light-emitting device, according to another embodiment ofthe present invention;

FIGS. 7A through 7C are cross-sectional views for explaining a method ofmanufacturing a semiconductor light-emitting device, according toanother embodiment of the present invention;

FIG. 8 is a cross-sectional view illustrating a semiconductorlight-emitting device according to another embodiment of the presentinvention;

FIGS. 9A through 9L are cross-sectional views for explaining a method ofmanufacturing a semiconductor light-emitting device, according toanother embodiment of the present invention;

FIGS. 10A through 10D are plan views illustrating electrode patterns ina process of manufacturing a semiconductor light-emitting device,according to an embodiment of the present invention;

FIG. 11 is a cross-sectional view illustrating a semiconductorlight-emitting device according to another embodiment of the presentinvention;

FIGS. 12A through 12G are cross-sectional views for explaining a methodof manufacturing a semiconductor light-emitting device, according toanother embodiment of the present invention; and

FIGS. 13A through 13C are plan views illustrating electrode patterns ina process of manufacturing a semiconductor light-emitting device,according to another embodiment of the present invention.

DETAILED DESCRIPTION

The present invention will now be described more fully with reference tothe accompanying drawings, in which exemplary embodiments of theinvention are shown. Thicknesses of layers or regions illustrated in thedrawings are exaggerated for clarity. In the drawings, the same elementsare denoted by the same reference numerals and a detailed explanationthereof will not be given.

FIG. 1A is a cross-sectional view illustrating a semiconductorlight-emitting device 100 according to an embodiment of the presentinvention. FIG. 1B is a modified example of the semiconductorlight-emitting device 100 of FIG. 1A. FIG. 2 is a cross-sectional viewtaken along line II-II′ of FIG. 1A.

Referring to FIGS. 1A and 2, the semiconductor light-emitting device 100includes a semiconductor structure 110, an electrode structure disposedon one surface of the semiconductor structure 110, and a substratesupporting the electrode structure.

The semiconductor structure 110 includes a substrate (not shown), and afirst semiconductor layer 111, an active layer 112, and a secondsemiconductor layer 113 sequentially formed by using crystal growth on asubstrate (not shown), for example, a sapphire substrate. The sapphiresubstrate may be removed during a manufacturing process and is not shownin FIG. 1A for convenience.

The semiconductor structure 110 is formed of III-V semiconductors suchas gallium nitride (GaN), indium nitride (InN), and aluminum nitride(AlN). Since the sapphire substrate has a lattice structure similar tothat of each of the nitride semiconductors, the sapphire substrate isused for crystal growth. The first semiconductor layer 111 may haven-type conductivity and the second semiconductor layer 113 may havep-type conductivity. Alternatively, the first semiconductor layer 111may have p-type conductivity and the second semiconductor layer 113 mayhave n-type conductivity.

The active layer 112 is located between the first semiconductor layer111 and the second semiconductor layer 113. The active layer 112 mayhave, for example, a multi-quantum well structure. The multi-quantumwell structure includes a plurality of quantum well layers and aplurality of quantum barrier layers formed between the quantum welllayers. In detail, if the semiconductor structure 110 is a galliumnitride-based light-emitting diode, the first semiconductor layer 111may be formed of GaN doped with n-type impurities, the secondsemiconductor layer 113 may be formed of GaN doped with p-typeimpurities, and the active layer 112 may be formed by alternatelystacking multi-well layers formed of InGaN and quantum barrier layersformed of GaN. Electrons and holes injected through the firstsemiconductor layer 111 and the second semiconductor layer 113 combinewith each other in the active layer 112 to emit light L. The emittedlight L is emitted through the first semiconductor layer 111 of thesemiconductor structure 110.

A second electrode layer 120, an insulating layer 130, a first electrodelayer 140, and a non-conductive substrate 150 are sequentially disposedunder the second semiconductor layer 113. A portion of the firstelectrode layer 140 passes through the insulating layer 130, the secondelectrode layer 120, the second semiconductor layer 113, and the activelayer 112, and extends through a contact hole 180 that reaches apredetermined region of the first semiconductor layer 111 to contact thefirst semiconductor layer 111. A plurality of the contact holes 180 maybe formed as shown in FIG. 2. The first electrode layer 140 filled inthe plurality of contact holes 180 may rapidly diffuse and supplycurrent to the first semiconductor layer 111.

The contact holes 180 may be arranged in a matrix in consideration ofcurrent spreading and light extraction. The contact holes 180 may bearranged at regular intervals in at least one direction from among ahorizontal direction and a vertical direction as shown in FIG. 2 or FIG.10A. If necessary, the contact holes 180 may be arranged randomly atdifferent intervals.

A size of each of the contact holes 180 may range from 0.1 to 500 μm,and preferably, may range from 5 to 300 μm. In the present embodiment,the contact hole 180 has a size ranging from 30 to 100 μm.

An area of a portion of the contact hole 180 contacting the firstsemiconductor layer 111 may range from 0.01 to 30% of an area of thefirst semiconductor layer 111 including the contact hole 180,preferably, may range from 0.9 to 10.4%, and more preferably, may beabout 2.6%. If an area of the contact hole 180 is less than 0.01%, sincean operating voltage is increased, light efficiency may be reduced andpower consumption may be increased. On the other hand, if an area of thecontact hole 180 is greater than 30%, an effective light-emitting areais relatively reduced. In the present embodiment, a regular square chiphaving lengths of 1100 μm in horizontal and vertical directions is used,and light efficiencies of three light-emitting devices including thecontact holes 180 that contact the first semiconductor layer 111 andhave areas of 11300 μm² (0.9% of an area of the regular square chip),31400 μm² (2.6% of an area of the regular square chip), and 126000 μm²(10.4% of an area of the regular square chip) are compared. The lightefficiency of the light-emitting device including the contact hole 180whose area is 31400 μm² (2.6% of an area of the regular square chip) isthe highest and the light efficiencies of the other two light-emittingdevices are lower than the highest light efficiency by about 10%.

A inclination angle ‘a’ between a bottom plane of the contact hole 180,which is parallel to the first semiconductor layer 111, and a sidesurface of the contact hole 180 is greater than 0 degrees and is lessthan 90 degrees, and preferably may be about 30 to 60 degrees. If theinclination angle ‘a’ is equal to or greater than 90 degrees, it may bedifficult to form the insulating layer 130 along the inclined sidesurface of the contact hole 180, and it may be difficult to form thefirst electrode layer 140. The inclined side surface of the contact hole180 may be stepped in order to improve light extraction efficiency, anda concavo-convex structure may be formed on the inclined side surface ofthe contact hole 180. A reflective material may be partially or entirelycoated on the inclined side surface. The reflective material may includeat least one selected from the group consisting of silver (Ag), aluminum(Al), platinum (Pt), nickel (Ni), palladium (Pd), titanium (Ti), gold(Au), iridium (Ir), tungsten (W), stannum (Sn), an oxide thereof, and amixture thereof, and may have a single-layer structure or a multi-layerstructure. The reflective material improves light extraction efficiency.

The insulating layer 130 for electrically insulating the first electrodelayer 140 from layers other than the first semiconductor layer 111 isformed between the first electrode layer 140 and the second electrodelayer 120. The insulating layer 130 is formed not only between the firstelectrode layer 140 and the second electrode layer 120 but also betweenthe first electrode layer 140 and side surfaces of the second electrodelayer 120, the second semiconductor layer 113, and the active layer 112exposed by the contact hole 180. Also, the insulating layer 130 may beformed on a side surface of the predetermined region of the firstsemiconductor layer 111 which the contact hole 180 reaches.

The second electrode layer 120 is formed to contact the secondsemiconductor layer 113. Since the second electrode layer 120electrically contacts the second semiconductor layer 113, the secondelectrode layer 120 is formed of a reflective material that may minimizecontact resistance to the second semiconductor layer 113 and improveluminous efficiency by reflecting light generated by the active layer112 to the outside. The second electrode layer 120 may be formed of atleast one material selected from the group consisting of Ag, Al, Pt, Ni,Pd, Ti, Au, Ir, W, Sn, an oxide thereof, and a mixture thereof, and hasa single-layer structure or a multi-layer structure. A thickness of eachlayer may range from 0.1 to 5000 nm, and preferably, may range from 2 to2000 nm. In the present embodiment, the second electrode layer 120 has a4-layer structure including Ag, Ni, Ti, and TiN layers, and thicknessesof the Ag, Ni, Ti, and TiN layers are respectively 150 nm, 50 nm, 50 nm,and 400 nm. If a thickness of the Ag layer of the second electrode layer120 is less than 40 nm, a reflectivity may be reduced and light outputmay be reduced. If a thickness of the Ag layer of the second electrodelayer 120 is greater than 150 nm, material costs may be increased and aprocessing time may be increased. Accordingly, it is preferable that athickness of the Ag layer of the second electrode layer 120 ranges from100 to 150 nm. After the second electrode layer 120 is formed, heattreatment is performed to form an ohmic contact. Good ohimiccharacteristics are obtained by performing rapid thermal annealing (RTA)as heat treatment at 350° C. for 60 seconds in the present embodiment.While a temperature and a time of heat treatment may vary according to amaterial of an ohmic electrode, the heat treatment may be performed at300 to 800° C. for 5 to 5000 seconds, and preferably, may be performedat 300 to 600° C. for 30 to 180 seconds.

A first through-hole 151 filled with a first contact 153 that suppliescurrent to the first electrode layer 140, and a second through-hole 152filled with a second contact 154 that supplies current to the secondelectrode layer 120 are formed in the non-conductive substrate 150. Thesecond through-hole 152 extends to pass through the first electrodelayer 140. An insulating layer 156 is further formed on an innercircumferential surface of the second through-hole 152 to electricallyinsulate the second contact 154 from the first electrode layer 140. Thefirst contact 153 is electrically connected to the first electrode layer140 passing through the non-conductive substrate 150. The second contact154 is electrically connected to the second electrode layer 120 passingthrough the non-conductive substrate 150, the first electrode layer 140and the insulating layer 130.

The non-conductive substrate 150 may include any one material selectedfrom the group consisting of a nitride-based material such as GaN, AlN,aluminum gallium nitride (AlGaN), or indium gallium nitride (InGaN), analuminum oxide-based material such as sapphire or alumina, diamond, asilicon-based material such as silicon (Si), a gallium (Ga) oxide-basedmaterial such as Ga₂O₃ or LiGaO₂, a zinc (Zn) oxide-based material suchas zinc oxide (ZnO), ceramic, and polymer.

Although the first contact 153 and the second contact 154 are formed inthe non-conductive substrate 150, the present embodiment is not limitedthereto. For example, a through-hole may be formed in a conductivesubstrate (see FIG. 4B), an insulating layer 460 (see FIG. 4B) may beformed on an inner circumferential surface of the through-hole and asurface of the conductive substrate, and a first contact 453 (see FIG.4B) and a second contact 454 (see FIG. 4B) may be filled with metals,which will be explained in detail with reference to FIGS. 4A through 4C.The conductive substrate may be formed of a Si-based material, agermanium (Ge)-based material, a Si material containing aluminum, or anitride-based material such as GaN.

As described above, according to the present embodiment, since anelectrode connected to a first semiconductor layer and a secondsemiconductor layer is formed on a lower surface of a light-emittingdevice, a light-emitting area is prevented from being reduced, therebymaximizing luminous efficiency. Also, since the electrode is formed on alower surface of a non-conductive substrate, direct package die bondingmay be performed without wire bonding.

FIG. 1B is a cross-sectional view illustrating a light-emitting device100′ that is a modified example of the light-emitting device 100 of FIG.1A. The same elements as those in FIG. 1A are denoted by the samereference numerals, and thus a detailed explanation thereof will not begiven.

Referring to FIG. 1B, a sapphire substrate 102 is disposed on the firstsemiconductor layer 111 of the semiconductor structure 110. The sapphiresubstrate 102 is a substrate on which the semiconductor structure 110 isgrown. A concavo-convex structure may be formed on a surface of thesapphire substrate 102. The concavo-convex structure may improve lightextraction efficiency of the light-emitting device 100′. Other elementsof the light-emitting device 100′ are substantially the same as those ofthe light-emitting device 100, and thus a detailed explanation thereofwill not be given.

FIGS. 3A through 3J are cross-sectional views for explaining a method ofmanufacturing a semiconductor light-emitting device, according to anembodiment of the present invention. Although a method of manufacturingone light-emitting device is illustrated in FIGS. 3A through 3J forconvenience of explanation, a plurality of light-emitting devices may beintegrally formed on a wafer and may be cut into individuallight-emitting devices, or a light-emitting device unit integrallyincluding a plurality of light-emitting devices may be manufactured.

Referring to FIG. 3A, a semiconductor structure 210 is formed bysequentially forming a first semiconductor layer 211, an active layer212, and a second semiconductor layer 213 by using crystal growth on atop surface of a substrate 202.

A substrate suitable for a semiconductor to be formed by using crystalgrowth may be selected as the substrate 202. For example, if a nitridesemiconductor single crystal is to be grown, the substrate 202 may beany one selected from the group consisting of a sapphire substrate, aZnO substrate, a GaN substrate, a silicon carbide (SiC) substrate, andan AlN substrate.

The substrate 202 may have a thickness of about 300 to 1200 μm accordingto a size. Various patterns may be formed on a surface or a rear surfaceof the substrate 202 according to a type of a material (e.g., a thermalexpansion coefficient) to be grown on the top surface of the substrate202. The patterns may reduce crystal defects during crystal growth, andreduce stress due to thermal expansion or the like. The patterns mayimprove light extraction efficiency. The patterns may have circular orpolygonal shapes (e.g., triangular shapes, square shapes, pentagonalshapes, or octagonal shapes) when viewed along a plane. The patterns mayhave semi-circular, circular conic, or polygonal cross-sectional shapes(e.g., triangular shapes, square shapes including trapezoidal shapes,pentagonal shapes, or hexagonal shapes). After crystal growth, thesubstrate 202 may be partially or entirely removed by a laser beam,chemical etching, or the like. A thickness of the substrate 202 mayrange from about 50 to 300 μm that is small, and a concavo-convexstructure may be formed on a surface of the substrate 202.

Although not shown in FIG. 3A, a buffer layer (not shown) may be furtherformed between the substrate 202 and the first semiconductor layer 211.The buffer layer is a layer for improving lattice matching between thesubstrate 202 and the first semiconductor layer 211. If a nitridesemiconductor single crystal is to be grown, the buffer layer may beformed of a material including any one selected from the groupconsisting of SiC, a nitride such as GaN, AlGaN, InGaN, InN, or AlInGaN,a Zn oxide, a Si oxide, and a combination thereof.

The buffer layer may be formed to a thickness of 2 to 800 nm at 400 to800° C. to have a single-layer structure or a multi-layer structure. Thebuffer layer may be formed of an amorphous material, a multi-crystallinematerial, or a mixture thereof. A single crystalline semiconductor layeris formed on a top surface of the buffer layer. For example, anamorphous or a multi-crystalline GaN buffer layer is formed at 500 to600° C. and then a single crystalline GaN layer is formed at 1000 to1200° C. In this process, at least one part of the amorphous ormulti-crystalline GaN buffer layer is single-crystallized. Thesemiconductor structure 210 may be formed by growing III-Vsemiconductors such as GaN, InN, and AlN. For example, if thesemiconductor structure 210 is a gallium nitride-based light-emittingdiode, the first semiconductor layer 211, the active layer 212, and thesecond semiconductor layer 213 may be formed of a semiconductor materialhaving a formula represented by Al_(x)In_(y)Ga_((1-x-y))N (where 0≦x≦1,0≦y≦1, and 0≦x+y≦1), and may be formed by using epitaxial growth usingmetal organic chemical vapor deposition (MOCVD) equipment. That is, thefirst semiconductor layer 211 may be a nitride semiconductor layer(formed of GaN, InN, InGaN, AlGaN, AlN, AlInGaN, or a combinationthereof) doped, non-doped, or combined with first conductive impuritiessuch as Si, Ge, or Sn. The active layer 212 may be a InGaN/GaN layer, aInGaN/InGaN layer, a AlGaN/GaN layer, a AlGaN/AlGaN layer, aAlInGaN/AlInGaN layer or a combination thereof having a multi-quantumwell structure, one quantum well layer structure, or a double heterostructure. The second semiconductor layer 213 may be s a nitridesemiconductor layer (formed of GaN, InN, InGaN, AlGaN, AlN, AlInGaN, ora combination thereof) doped with, non-doped with, or combined withsecond conductive impurities such as magnesium (Mg), zinc (Zn), orberyllium (Be). The first semiconductor layer 211, the active layer 212,and the second semiconductor layer 213 may have various thicknesses(ranging from 1 to 10000 nm) or impurity concentrations (ranging from1×10¹⁵/cm³ to 1×10²²/cm³) according to functions of the firstsemiconductor layer 211, the active layer 212, and the secondsemiconductor layer 213.

Referring to FIG. 3B, a contact hole 210 a is formed by using etching toa predetermined depth (from 0.5 to 20 μm) of the first semiconductorlayer 211 from the second semiconductor layer 213 by using dry etching(e.g., inductively-coupled plasma reactive ion etching (ICP-RIE)) and/orwet etching. The contact hole 210 a is formed by removing the secondsemiconductor layer 213 and the active layer 212 to expose at least asurface of the first semiconductor layer 211. A portion of the firstsemiconductor layer 211 may be etched to a predetermined depth (0.1 nmto 5000 nm), and if necessary, a through-hole may be formed. A size(diameter) of the contact hole 210 a may range from 0.1 to 500 μm, andpreferably, may range from 5 to 300 μm. A plurality of the contact holes210 a may be formed. An area of a portion of the contact hole 210 acontacting the first semiconductor layer 211 may range from 0.01 to 30%of an area of the first semiconductor layer 211 including the contacthole 210 a, preferably may range from 0.9% to 10.4%, and morepreferably, may be about 2.6%. An inclination angle ‘a’ between a bottomplane of the contact hole 210 a, which is parallel to the firstsemiconductor layer 211, and a side surface of the contact hole 210 amay be greater than 0 degrees and less than 90 degrees, and preferably,may range from about 30 to 60 degrees. If the inclination angle ‘a’ isgreater than 90 degrees, it may be difficult to form an insulating layer221 and it may be difficult to form a first electrode layer that will bedescribed later. The inclined side surface of the contact hole 210 a maybe stepped in order to improve light extraction efficiency, and aconcavo-convex structure may be formed on the inclined side surface.Also, a reflective material may be partially or entirely coated on theinclined side surface. The reflective material may include at least oneselected from the group consisting of Ag, Al, Pt, Ni, Pd, Ti, Au, Ir, W,Sn, an oxide thereof, and a mixture there, and may have a single-layerstructure or a multi-layer structure. The reflective material improveslight extraction efficiency.

The insulating layer 221 is coated by using deposition on an entire topsurface of the semiconductor structure 210 including the contact hole210 a. For example, the insulating layer 221 may be formed by depositingSiO₂ or SiN_(x) by using plasma enhanced chemical vapor deposition(PECVD). The insulating layer 221 may be formed to a thickness of 0.001to 50 μm, and preferably, to a thickness of 0.3 to 1.2 μm. Referring toFIG. 3C, a portion of the first semiconductor layer 211 is exposed byetching a portion of the insulating layer 221 formed on a bottom of thecontact hole 210 a. The etching may be performed by using RIE dryetching or wet etching using a buffered oxide etchant (BOE).

A contact layer 231 is formed on the exposed portion of the firstsemiconductor layer 211. The contact layer 231 is formed of a materialthat may form an ohmic contact with the first semiconductor layer 211and have a high reflectivity. For example, the contact layer 231 may beformed of a material including at least one selected from the groupconsisting Al, Ti, Pt, Ag, Ni, TiN, Au, Sn, and a mixture thereof andmay have a single-layer structure or a multi-layer structure. Athickness of each layer may range from 0.1 to 5000 nm. For example, inthe present embodiment, the contact layer 231 is formed by depositing aAl/Ti/Pt/Ti layer to a thickness of 200 nm/300 nm/100 nm/2 nm. In thiscase, current spreading to the first semiconductor layer 211 may beimproved by forming a plurality of the first electrode layers 231 asshown in FIG. 2 or FIG. 10A. The plurality of contact layers 231 may bearranged in a matrix. After the contact layer 231 is formed, heattreatment for forming an ohmic contact is performed. Good ohmiccharacteristics are obtained by performing RTA as heat treatment at 550°C. for 60 seconds. While a temperature and a time of heat treatment mayvary according to a material of an ohmic electrode, the heat treatmentmay be performed at 300 to 800° C. for about 5 to 5000 seconds, andpreferably, may be performed at 300 to 600° C. for 30 to 180 seconds.

An insulating layer 222 is formed on the second semiconductor layer 213to be filled between the insulating layer 221 and the contact layer 231in the contact hole 210 a. The insulating layer 222 may be formed of thesame material as that of the insulating layer 221.

Referring to FIG. 3D, the second semiconductor layer 213 is exposed byetching a portion of the insulating layers 221 and 222 other than aportion that surrounds the contact hole 210 a. The etching may beperformed by performing RIE dry etching or wet etching using a BOE.

The insulating layer 221 and the insulating layer 222 may becollectively referred to as an insulating layer 220 herein below forconvenience.

Referring to FIG. 3E, a second electrode layer 240 is formed on theexposed second semiconductor layer 213. The second electrode layer 240may be formed of a metal that has both ohmic characteristics and lightreflecting characteristics to act as a reflective layer, or may have amulti-layer structure formed by sequentially stacking metals havingohmic characteristics and light reflecting characteristics. The secondelectrode layer 240 may be formed of at least one material selected fromthe group consisting of Ag, Al, Pt, Ni, Pd, Ti, Au, Ir, W, Sn, an oxidethereof, and a mixture thereof, and may have a single-layer structure ora multi-layer structure. These materials improve light extractionefficiency.

An insulating layer 223 is formed on the second electrode layer 240 to apredetermined thickness. The insulating layer 223 may be formed bydepositing SiO₂ by using, for example, PECVD. Referring to FIG. 3F, thecontact layer 231 is exposed by etching the insulating layer 220. Afirst electrode layer 230 connected to the exposed contact layer 231 isformed by coating a metal material on the insulating layer 220. Thefirst electrode layer 230 is formed by repeatedly stacking a layerhaving a structure of Ti (100 nm)/Ni (100 nm) four times andadditionally stacking a Ti (100 nm)/Au (1500 nm)/Sn (1400 nm)/Au (10 nm)layer.

Referring to FIG. 3G, a non-conductive substrate 250 is bonded to thefirst electrode layer 230. The non-conductive substrate 250 may be analumina substrate, an AlN substrate, a sapphire substrate, a ceramicsubstrate, or a polymer substrate. In order to adhere the non-conductivesubstrate 250 to the first electrode layer 230, a conductive adhesivematerial or a non-conductive adhesive material may be used as a mediumbetween the non-conductive substrate 250 and the first electrode layer230. The conductive adhesive material may include at least one selectedfrom the group consisting of AuSn, Au, Cu, Pb, W, Ti, Pt, Sn, TiSn, anda mixture thereof and have a single-layer structure or a multi-layerstructure. The non-conductive adhesive material may be silicon-on-glass(SOG), or polymer.

Referring to FIG. 3H, the substrate 202 is removed from the firstsemiconductor layer 211. For example, the substrate 202 may be separatedfrom the first semiconductor layer 211 by irradiating laser light ontothe substrate 202 to cause thermal reaction between the substrate 202and the first semiconductor layer 211. The substrate 202 is removed bybeing lifted off from the first semiconductor layer 211. The substrate202 may be removed by performing chemical etching or chemical-mechanicalpolishing.

Referring to FIG. 3I, a first through-hole 251 and a second through-hole252 respectively connected to the first electrode layer 230 and thesecond electrode layer 240 are formed from an exposed surface of thenon-conductive substrate 250. A thickness of the substrate 250 may rangefrom 50 to 300 μm, and preferably, may range from 100 to 200 μm. If athickness of the substrate 250 is too great, it takes a long time toform the first and second through-holes 251 and 252, and if a thicknessof the substrate 250 is too small, the substrate 250 may notsufficiently act as a support substrate.

A size of each of the first and second through-holes 251 and 252 mayrange from 0.1 to 500 μm, and preferably, may range from 5 to 300 μm.One or more first and second through-holes 251 and 252 may be formed. Anarea of each of the first and second through-holes 251 and 252 may rangefrom about 0.01 to 30% of an area of a bottom surface 250 a of thesubstrate 250. The first and second through-holes 251 and 252 may bestepped or tapered with respect to the bottom surface 250 a. Referringto FIG. 3J, an insulating layer 256 is formed on a side surface of thesecond through-hole 252. In this case, an insulating layer (not shown)may also be formed on a side surface of the first through-hole 251. Afirst contact 253 and a second contact 254 formed of metals are formedin the first through-hole 251 and the second through-hole 252,respectively. The first through-hole 251 and the second through-hole 252may be formed by using laser drilling, dry etching, or wet etching.

FIGS. 4A through 4C are cross-sectional views for explaining a method ofmanufacturing a semiconductor light-emitting device, according toanother embodiment of the present invention.

The same processes as those of FIGS. 3A through 3F may be performed, andthus a detailed explanation thereof will not be given.

Referring to FIG. 4A, in a resultant structure formed by the processesof FIGS. 3A through 3F, a through-hole 441 connected to the secondelectrode layer 240 is formed from an exposed surface of the firstelectrode layer 230. An insulating layer 442 is formed on a side surfaceof the through-hole 441. A contact 443 formed of a metal is formed inthe through-hole 441. The through-hole 441 may be formed by using laserdrilling or dry etching. A thickness of the first electrode layer 230may range from 0.1 to 300 μm, and preferably, may range from 0.5 to 100μm. If a thickness of the first electrode layer 230 is greater than 300μm, it may take a long time to form the through-hole 441 and costs maybe increased. If a thickness of the first electrode layer 230 is lessthan 0.1 μm, the first electrode layer 230 may not sufficiently act asan adhesive layer. A size (diameter) of the through-hole 441 may rangefrom 0.1 to 500 μm, and preferably, may range from 5 to 300 μm. In thepresent embodiment, the through-hole 441 has a size ranging from 30 to100 μm. One or more through-holes 441 may be formed. An area of thethrough-hole 441 may range from 0.01 to 30% of an area of the firstelectrode layer 230. The through-hole 441 may be stepped or tapered withrespect to a top surface 230 a of the first electrode layer 230.

The insulating layer 442 may have a thickness ranging from 0.001 to 50μm, and a thickness of the insulating layer 442 may preferably rangefrom about 0.01 to 30% of a diameter of the through-hole 441. In thepresent embodiment, the insulating layer 442 has a thickness rangingfrom 0.01 to 0.9 μm.

Referring to FIG. 4B, a first through-hole 451 and a second through-hole452 are formed in a conductive substrate 450. The second through-hole452 is formed to correspond to the through-hole 441, and the firstthrough-hole 451 is formed to be spaced apart from the secondthrough-hole 452. The conductive substrate 450 may be formed of Si, Ge,or silicon containing a metal (for example, Al).

An insulating layer 460 is formed on a surface of the conductivesubstrate 450 including inner circumferential surfaces of the firstthrough-hole 451 and the second through-hole 452.

A first contact 453 and a second contact 454 are formed by filling thefirst through-hole 451 and the second through-hole 452 with metals,respectively.

Referring to FIG. 4C, the conductive substrate 450 is bonded to thefirst electrode layer 230 such that the second contact 454 of theconductive substrate 450 contacts the contact 443. In order to adherethe conductive substrate 450 to the first electrode 230, a conductiveadhesive material (not shown) may be formed on the first contact 453 andthe second contact 454, and a non-conductive adhesive material (notshown) may be formed on other portions. The conductive adhesive materialmay include at least one selected from the group consisting AuSn, Au,Cu, Pb, W, Ti, Pt, Sn, TiSn, and a mixture thereof, and may have asingle-layer structure or a multi-layer structure. The non-conductiveadhesive material may be SOG or polymer.

The substrate 202 is removed from the first semiconductor layer 211. Forexample, the substrate 202 may be separated from the first semiconductorlayer 211 by irradiating laser light onto the substrate 202 to causethermal reaction between the substrate 202 and the first semiconductorlayer 211. The substrate 202 is removed by being lifted off from thefirst semiconductor layer 211. Alternatively, the substrate 202 may beremoved by performing chemical etching or chemical-mechanical polishing.The substrate 200 may be used without being removed by reducing athickness of the substrate 202 or by forming a concavo-convex structureon a surface of the substrate 202.

Although the conductive substrate 450 is used in the method of FIGS. 4Athrough 4C, the non-conductive substrate 250 may be used in the methodand a detailed explanation thereof will not be given.

FIG. 5 is a cross-sectional view illustrating a semiconductorlight-emitting device 500 according to another embodiment of the presentinvention.

Referring to FIG. 5, the semiconductor light-emitting device 500includes a semiconductor structure 510, an electrode structure disposedon one surface of the semiconductor structure 510, and a substrate 560supporting the electrode structure.

The semiconductor structure 510 includes a substrate (not shown), and afirst semiconductor layer 511, an active layer 512, and a secondsemiconductor layer 513 sequentially formed by using crystal growth onthe substrate, for example, a sapphire substrate. Since the sapphiresubstrate is removed in a manufacturing process, the sapphire substrateis not shown in FIG. 5.

The semiconductor structure 510 is formed of gallium nitride-based III-Vsemiconductors such as GaN, InN, InGaN, AlGaN, AlN, AlInGaN, and acombination thereof. Since the sapphire substrate has a latticestructure similar to that of each of the nitride semiconductors, thesapphire substrate is used for crystal growth. The first semiconductorlayer 511 may have n-type conductivity and the second semiconductorlayer 513 may have p-type conductivity. Alternatively, the firstsemiconductor layer 511 may have p-type conductivity and the secondsemiconductor layer 513 may have n-type conductivity.

The active layer 512 is located between the first semiconductor layer511 and the second semiconductor layer 513. The active layer 512 mayhave, for example, a single or multi-quantum well structure. Electronsand holes injected through the first semiconductor layer 511 and thesecond semiconductor layer 513 combine with each other in the activelayer 512 to emit light L. The emitted light L is emitted through thefirst semiconductor layer 511 of the semiconductor structure 510.

A second electrode layer 520, an insulating layer 530, a first electrodelayer 540, and the substrate 560 are sequentially disposed under thesecond semiconductor layer 513. A portion of the first electrode layer540 passes through the insulating layer 530, the second electrode layer520, the second semiconductor layer 513, and the active layer 512, andextends through a contact hole 580 that reaches a predetermined regionof the first semiconductor layer 511 to contact the first semiconductorlayer 511. A plurality of the contact holes 580 may be formed as shownin FIG. 2. The first electrode layer 540 filled in the plurality ofcontact holes 580 may rapidly diffuse and supply current to the firstsemiconductor layer 511.

The contact hole 580 is formed by removing the second semiconductorlayer 513 and the active layer 512 to expose at least a surface of thefirst semiconductor layer 511. A portion of the first semiconductorlayer 511 may be etched to a predetermined depth (0.1 to 5000 nm), andif necessary, a through-hole may be formed. A size (diameter) of thecontact hole 580 may range from 0.1 to 500 μm, and preferably, may rangefrom 5 to 300 μm. A plurality of the contact holes 580 may be formed. Anarea of a portion of the contact hole 580 contacting the firstsemiconductor layer 511 may range from 0.01 to 30% of an area of thefirst semiconductor layer 511 including the contact hole 580, preferablymay range from 0.9 to 10.4%, and more preferably, may be about 2.6%. Aconcavo-convex structure may be formed on a bottom of the contact hole580. An inclination angle ‘a’ between a bottom plane of the contact hole580, which is parallel to the first semiconductor layer 511, and a sidesurface of the contact hole 580 may be greater than 0 degrees and lessthan 90 degrees, and preferably, may range from about 30 to 60 degrees.If the inclination angle ‘a’ is greater than 90 degrees, it may bedifficult to form the insulating layer 530 on the inclined side surfaceand it may be difficult to form the first electrode layer 540. Theinclined side surface of the contact hole 580 may be stepped in order toimprove light extraction efficiency, and a concavo-convex structure maybe formed on the inclined side surface. Also, a reflective material maybe partially or entirely coated on the inclined side surface. Thereflective material may include at least one selected from the groupconsisting of Ag, Al, Pt, Ni, Pd, Ti, Au, Ir, W, Sn, an oxide thereof,and a mixture there, and may have a single-layer structure or amulti-layer structure. The reflective material improves light extractionefficiency.

The insulating layer 530 for electrically insulating the first electrodelayer 540 from layers other than the first semiconductor layer 511 isformed between the first electrode layer 540 and the second electrodelayer 520. The insulating layer 530 is formed not only between the firstelectrode layer 540 and the second electrode layer 520 but also betweenthe first electrode layer 540 and side surfaces of the second electrodelayer 520, the second semiconductor layer 513, and the active layer 512exposed by the contact hole 580. Also, the insulating layer 530 may alsobe formed on a side surface of the predetermined region of the firstsemiconductor layer 511 which the contact hole 580 reaches. Theinsulating layer 530 may have a thickness ranging from 0.001 to 50 μm,and a thickness of the insulating layer 53 may preferably range fromabout 0.001 to 30% of a diameter of the contact hole 580. In the presentembodiment, the insulating layer 530 has a thickness ranging from 0.01to 0.9 μm.

The second electrode layer 520 is formed to contact the secondsemiconductor layer 513. The second electrode layer 550 does not existin predetermined regions through which the contact hole 580 passes.Since the second electrode layer 520 electrically contacts the secondsemiconductor layer 513, the second electrode layer 520 is formed of amaterial that may minimize contact resistance to the secondsemiconductor layer 513 and improve luminous efficiency by reflectinglight generated by the active layer 512 to the outside. The secondelectrode layer 520 may be formed of at least one material selected fromthe group consisting of Ag, Al, Pt, Ni, Pd, Ti, Au, Ir, W, Sn, an oxidethereof, and a mixture thereof. A first electrode pad 551 is formedunder a portion of the first electrode layer 540, and an insulatinglayer 534 is formed on the other portion of the first electrode layer540. The insulating layer 534 contacts the insulating layer 530. Asecond electrode pad 552 is formed under a portion of the secondelectrode layer 520 where the insulating layer is not formed. The secondelectrode pad 552 is electrically connected to the second electrodelayer 520. The second electrode pad 552 is spaced apart from the firstelectrode 551 by a gap 554 therebetween. The second electrode pad 552may be spaced apart from the first electrode pad 551 and may be formedat the vertically same position as the first electrode pad 551. Areascovered by the second electrode pad 552 and the first electrode pad 551may be designed according to needs.

Each of the first and second electrode pads 551 and 552 may be formed ofa material including at least one selected from the group consisting ofAuSn, Au, Al, Ni, Cu, Pb, W, Ti, Pt, Sn, TiSn, and a mixture thereof.Each of the first and second electrode pads 551 and 552 may have asingle-layer structure or a multi-layer structure including a pluralityof layers formed of different materials. A thickness of each of thefirst and second electrode pads 551 and 552 may range from 0.1 to 500μm. It is preferable that the first electrode pad 551 has an area equalto or greater than that of the second electrode pad 552 in considerationof heat dissipation or the like.

The gap 554 may be filled with an insulating material (not shown).

The substrate 560 is attached to bottom surfaces of the first electrodepad 551 and the second electrode pad 552. A first through-hole 561 and asecond through-hole 562 spaced apart from each other are formed in thesubstrate 560. A first contact 563 and a second contact 564 arerespectively formed in the first through-hole 561 and the secondthrough-hole 562. The first contact 563 and the second contact 564 arerespectively connected to the first electrode pad 551 and the secondelectrode pad 552. If the substrate 560 is a conductive substrate, aninsulating layer 570 is further formed such that the substrate 560 isinsulated from the first and second contacts 563 and 564 and the firstand second electrode pads 551 and 552.

Since a portion of the second electrode pad 552 contacting the secondcontact 564 is wide, the substrate 560 of the semiconductorlight-emitting device 500 may be easily bonded to the second electrodepad 552. Also, a position and an area of each of the first and secondelectrode pads 551 and 552 may be easily changed in order to cause theelectrode pad to contact the substrate 560 including a contact. An areaof the second electrode pad 552 is equal to or greater than 1.2 times anarea of the second contact 564 in order to facilitate contact betweenthe second electrode pad 552 and the second contact 564. An area of thefirst electrode pad 551 may be equal to or greater than 1.2 times anarea of the first contact 563 in order to facilitate contact between thefirst electrode pad 551 and the first contact 563.

FIGS. 6A through 6G are views for explaining a method of manufacturing asemiconductor light-emitting device, according to another embodiment ofthe present invention. The same processes as those of FIGS. 3A through3E may be performed, and the same elements as those in FIGS. 3A through3E are denoted by the same reference numerals and a detailed explanationthereof will not be given.

In FIG. 6A, two contact layers 231 are illustrated for convenience.Referring to FIG. 6A, the contact layer 231 is exposed by etching theinsulating layer 223. A photoresist 632 is formed in a first region A1of the second electrode layer 240 on the insulating layer 223, and afirst electrode layer 630 connected to the exposed contact layer 231 isformed by coating a metal material on a second region A2 exposed by thephotoresist 632.

Referring to FIG. 6B, the photoresist 632 is removed, and an insulatinglayer 634 is formed on the insulating layer 223 to cover the firstelectrode layer 630.

Referring to FIG. 6C, the second electrode layer 240 is exposed bypatterning the insulating layers 634 and 223 in the first region A1, andthen a second electrode pad 652 connected to the exposed secondelectrode layer 240 is formed. The second electrode pad 652 is formed tocover a portion of the insulating layer 634 in the second region A2, toincrease a second electrode pad forming area.

Referring to FIG. 6D, the first electrode layer 630 is exposed to bespaced apart from the second electrode pad 652 by etching a portion ofthe insulating layer 634 in the second region A2, and then a firstelectrode pad 651 is formed on the exposed first electrode layer 630. Asurface of the first electrode pad 651 and a surface of the secondelectrode pad 652 may be on the same horizontal level.

FIG. 6E is a plan view of a resultant structure of FIG. 6D. Referring toFIG. 6E, the first electrode pad 651 and the second electrode pad 652are spaced apart from each other. The first electrode pad 651 and thesecond electrode pad 652 may be easily designed irrespective of areas ofthe first electrode layer 630 and the second electrode layer 240.Accordingly, electrical connection with an electrode formed on apreviously prepared substrate may be facilitated.

Referring to FIG. 6F, a first through-hole 661 and a second through-hole662 are formed in a second substrate 660. The first through-hole 661 andthe second through-hole 662 are formed to correspond to the firstelectrode pad 651 and the second electrode pad 652, respectively.

The second substrate 660 may be formed of a conductive material such asSi, Ge, or silicon containing a metal (for example, silicon containingAl). An insulating layer 670 is formed on a surface of the secondsubstrate 660 including inner circumferential surfaces of the firstthrough-hole 661 and the second through-hole 662.

If the second substrate 660 is a non-conductive substrate formed of anon-conductive material such as alumina, aluminum nitride, or sapphire,a process of forming the insulating layer 670 may be omitted.

A first contact 663 and a second contact 664 are formed by filling thefirst through-hole 661 and the second through-hole 662 with metals.

Referring to FIG. 6G, the first contact 663 and the second contact 664of the second substrate 660 are bonded to the first electrode pad 651and the second electrode pad 652 to contact the first electrode pad 651and the second electrode pad 652, respectively. Next, the substrate 202is removed from the first semiconductor layer 211.

A gap 654 for separating the first electrode pad 651 from the secondelectrode pad 652 may be filled with an insulating layer (not shown). Amaterial and a structure of a semiconductor layer, a material and a sizeof an electrode, and so on which are the same as those in the aforesaidembodiments will not be explained. FIGS. 7A through 7C arecross-sectional views for explaining a method of manufacturing asemiconductor light-emitting device, according to another embodiment ofthe present invention.

Referring to FIG. 7A, a semiconductor structure 710 is formed bysequentially forming a first semiconductor layer 711, an active layer712, and a second semiconductor layer 713 by using crystal growth on atop surface of a substrate 702. A substrate suitable for a semiconductorto be formed by using crystal growth may be selected as the substrate702. For example, if a nitride semiconductor single crystal is to begrown, the substrate 702 may be any one of a sapphire substrate, a ZnOsubstrate, a GaN substrate, a SiC substrate, and an AlN substrate.

Next, a second electrode layer 740 is formed on the second semiconductorlayer 713.

Referring to FIG. 7B, a contact hole 710 a is formed by using etching toa predetermined depth of the first semiconductor layer 711 from thesecond electrode layer 740 by using ICP-RIE. An insulating layer 721 iscoated by using deposition on an entire top surface of the semiconductorstructure 710 including the contact hole 710 a. For example, theinsulating layer 721 may be formed by depositing SiO₂ or SiN_(x) byusing PECVD. A detailed manufacturing process is the same as thatdescribed above.

Referring to FIG. 7C, a portion of the first semiconductor layer 711 isexposed by etching a portion of the insulating layer 721 formed on abottom of the contact hole 710 a. The etching may be performed by usingRIE dry etching or wet etching using a BOE.

A first electrode layer 730 is formed on the insulating layer 721 tocover the exposed portion of the first semiconductor layer 711.

A step of forming another substrate on the first electrode layer 730 andremoving the substrate 702, and a step of forming a first contact and asecond contact connected to the first electrode layer 730 and the secondelectrode layer 740 on the another substrate may be inferred byreferring to a manufacturing process using a non-conductive substrate(FIGS. 3G through 3J) or a manufacturing process using a conductivesubstrate (FIGS. 4A through 4C), and thus a detailed explanation thereofwill not be given.

Also, a process of forming an electrode pad on the first electrode layer730 and forming another substrate may be inferred by referring to FIGS.6A through 6G, and thus a detailed explanation thereof will not begiven.

FIG. 8 is a cross-sectional view illustrating a semiconductorlight-emitting device 800 according to another embodiment of the presentinvention.

Referring to FIG. 8, the semiconductor light-emitting device 800includes a semiconductor structure 810, and an electrode structuredisposed on one surface 810 b of the semiconductor structure 810.

The semiconductor structure 810 includes a first semiconductor layer811, an active layer 812, and a second semiconductor layer 813 formed byusing crystal growth on a predetermined substrate 802 (see FIG. 9A). Thesubstrate 802 which is a base on which crystal growth occurs may beremoved as will be described later.

Electrons and holes injected through the first semiconductor layer 811and the second semiconductor layer 813 combine with each other in theactive layer 812 to emit light L. The emitted light L is emitted throughanother surface 810 c of the semiconductor structure 810.

The electrode structure includes a first electrode layer 830 and asecond electrode layer 840 disposed on the second semiconductor layer813, and a plating electrode layer 870 electrically connected to thefirst electrode layer 830 and the second electrode layer 840.

The first electrode layer 830 is electrically connected to the firstsemiconductor layer 811 through a contact hole 810 a extended to thefirst semiconductor layer 811 from the second semiconductor layer 813.The contact hole 810 a may be formed by using etching into a mesastructure or a vertical structure. A side surface of the contact hole810 a may be slanted to the stacked direction of the first semiconductorlayer 811, the active layer 812, and the second semiconductor layer 813.A plurality of the contact holes 810 a may be formed. For example,current spreading may be improved by forming the plurality of firstelectrode layers 830 as shown in FIG. 10A.

The second electrode layer 840 is disposed on the second semiconductorlayer 813, and is electrically connected to the second semiconductorlayer 813. The second electrode layer 840 may be disposed on a portionof the second semiconductor layer 813 (see FIG. 10B) where the contacthole 810 a is not formed.

An insulating layer 820 is formed on the side surface of the contacthole 810 a. The insulating layer 820 is coated on a portion of a topsurface of the semiconductor structure 810 other than a portion wherethe first electrode layer 830 is located and a portion where the secondelectrode layer 840 is located. The first electrode layer 830 isinsulated from the active layer 812, the second semiconductor layer 813,and the second electrode layer 840 due to the insulating layer 820.

The plating electrode layer 870 is disposed on the insulating layer 820.The plating electrode layer 870 includes a first electrode pad 871 and asecond electrode pad 872 with an insulating barrier 880 therebetween.The first electrode pad 871 is disposed in a first electrode regionwhere the first electrode layer 830 is located, and the second electrodepad 872 is disposed in a second electrode region where the secondelectrode layer 840 is located. The first electrode pad 871 and thesecond electrode pad 872 may be separated from each other by theinsulating barrier 880. The insulating barrier 880 may be formed of ageneral insulating material, for example, polyimide.

The plating electrode layer 870 may be formed by plating a metal such ascopper, nickel, or chromium to a thickness of tens of μm. In order toeasily perform plating, a seed layer 850 may be disposed under the firstelectrode pad 871 and the second electrode pad 872.

Since the plating electrode layer 870 formed by using plating asdescribed above provides electrical wiring and physical support to thesemiconductor structure 810, the semiconductor light-emitting device 800may easily achieve mass production and large scale fabrication andreduce manufacturing costs, unlike a conventional semiconductorlight-emitting device that provides electrical wiring and physicalsupport to the semiconductor structure 810 by bonding the semiconductorstructure 810 to an electrode substrate.

Next, a method of manufacturing a semiconductor light-emitting device,according to another embodiment of the present invention, will beexplained.

FIGS. 9A through 9K are cross-sectional views for explaining a method ofmanufacturing a semiconductor light-emitting device, according toanother embodiment of the present invention. FIGS. 10A through 10D areplan views illustrating electrode patterns in a process of manufacturinga semiconductor light-emitting device, according to an embodiment of thepresent invention.

Referring to FIG. 9A, the semiconductor structure 810 is formed bysequentially forming the first semiconductor layer 811, the active layer812, and the second semiconductor layer 813 by using crystal growth on atop surface of the substrate 802. Although not shown in FIG. 9A, abuffer layer (not shown) may be formed between the substrate 802 and thefirst semiconductor layer 811.

Referring to FIG. 9B, a portion of the first semiconductor layer 811 isexposed by forming the contact hole 810 a by using etching to apredetermined depth from the second semiconductor layer 813. In thiscase, a plurality of the contact holes 810 a may be formed to correspondto a plurality of the first electrode layers 830.

Next, a passivation layer 821 is coated by using deposition on an entiretop surface of the semiconductor structure 810 including the contacthole 810 a. For example, the passivation layer 821 may be formed bydepositing SiO₂ to about 6000 Å by using PECVD.

Referring to FIG. 9C, a portion of the first semiconductor layer 811 isexposed by etching a portion of the passivation layer 821 formed on abottom of the contact hole 810 a. The etching may be performed by usingRIE and a BOE. Next, the first electrode layer 830 is formed on theexposed portion of the first semiconductor layer 811.

The first electrode layer 830 may be formed of a material including atleast one selected from the group consisting Al, Ti, Pt, Ag, Ni, TiN,Au, Sn, and a mixture thereof, and may have a single-layer structure ora multi-layer structure including a plurality of layers formed ofdifferent materials. A thickness of each layer may range from 0.1 to5000 nm. For example, the first electrode layer 830 may be formed bydepositing a Al/Ti/Pt/Ti layer to a thickness of 200 nm/300 nm/100 nm/2nm in the present embodiment. In this case, current spreading to thefirst semiconductor layer 811 may be improved by forming a plurality ofthe first electrode layers 830 as shown in FIG. 10A. The plurality offirst electrode layers 830 may be arranged in a matrix, in order toachieve optimal current spreading. After the first electrode layer 830is formed, heat treatment for forming an ohmic contact is performed. Inthe present embodiment, good ohmic characteristics are obtained byperforming RTA as heat treatment at 550° C. for 60 seconds. While atemperature and a time of heat treatment may vary according to amaterial of an ohmic electrode, the heat treatment may be performed at300 to 800° C. for about 5 to 5000 seconds, and preferably, may beperformed at 300 to 600° C. for about 30 to 180 seconds.

The contact holes 180 may be arranged in a matrix in consideration ofcurrent spreading and light extraction.

Referring to FIG. 9D, the second semiconductor layer 813 is exposed byetching a portion of the passivation layer 821 other than a portion thatsurrounds the first electrode layer 830. The etching may be performed byusing RIE or a BOE. Next, the second electrode layer 840 is formed onthe exposed second semiconductor layer 813. In this case, the secondelectrode layer 840 is formed to be spaced apart from the firstelectrode layer 830 as shown in FIG. 10B. The second electrode layer 840may be formed of a metal that has both ohmic characteristics and lightreflecting characteristics to act as a reflective layer, or may have amulti-layer structure by formed sequentially stacking metals havingohmic characteristics and light reflecting characteristics. For example,the second electrode layer 840 may be formed by depositing aAg/Ni/Ti/TiN layer to a thickness of 150 nm/50 nm/50 nm/400 nm. Afterthe second electrode layer 840 is formed, heat treatment for forming anohmic contact is performed. Good ohmic characteristics are obtained byperforming RTA as heat treatment at 350° C. for 60 seconds in thepresent embodiment. While a temperature and a time of heat treatment mayvary according to a material of an ohmic electrode, the heat treatmentmay be performed at 300 to 800° C. for about 5 to 5000 seconds, andpreferably, may be performed at 300 to 600° C. for 30 to 180 seconds.

Referring to FIG. 9E, an insulating material layer 822 is coated to apredetermined thickness on a top surface of the semiconductor structure810. The insulating material layer 822 is coated on entire top surfacesof the first electrode layer 830, the second electrode layer 840, andthe passivation layer 821. The insulating material layer 822 may beformed by depositing SiO₂ to a thickness of about 8000 Å by using PECVD.The passivation layer 821 and the insulating material layer 822 may beformed of the same material, and may constitute the insulating layer 820that insulates the first electrode layer 830 from the second electrodelayer 840. A thickness of the insulating material layer 822 is greatenough to cover a top surface of the first electrode layer 830, and maypreferably range from 100 to 10000 nm. A thickness of the insulatinglayer 820 may range from 200 to 20000 nm. Referring to FIG. 9F, thefirst electrode layer 830 and the second electrode layer 840 are exposedby etching the insulating layer 820. In this case, if a plurality of thefirst electrode layers 830 are formed, all of the first electrode layers830 are exposed as shown in FIG. 10C. Meanwhile, only a predeterminedportion of the second electrode layer 840 may be exposed. The exposedfirst electrode layer 830 and second electrode layer 840 may be filledwith metal materials 835 and 845 such as copper, nickel, or chromium. Ifa plurality of the first electrode layers 830 are formed, the metalmaterial 835 may be formed to connect the plurality of first electrodelayers 830. This process may be inferred from a process illustrated inFIG. 3F, and thus a detailed explanation thereof will not be given.

Referring to FIG. 9G, the seed layer 850 for plating is formed on thefirst electrode layer 830 and the second electrode layer 840.

Referring to FIG. 9H, a photoresist 860 is formed on the seed layer 850.The photoresist 860 is formed over the insulating layer 820.

Referring to FIG. 9I, the plating electrode layer 870 is formed by usingplating on the seed layer 850. The plating electrode layer 870 includesthe first electrode pad 871 and the second electrode pad 872 with thephotoresist 860 therebetween. Each of the first electrode pad 871 andthe second electrode pad 872 may be formed to a thickness of 5 to 500 μmand may be formed of a metal such as copper, nickel, or chromium. Thefirst electrode pad 871 and the second electrode pad 872 are formed withthe photoresist 860 therebetween as shown in FIG. 10D.

Referring to FIG. 9J, a gap 870 a is formed between the first electrodepad 871 and the second electrode pad 872 by removing the photoresist860.

Referring to FIGS. 9K and 9L, the seed layer 850 is divided into a firstseed layer 851 and a second seed layer 852 by etching the seed layer850. The first seed layer 851 forms the insulating barrier 880 byfilling the gap 870 a where the photoresist 860 is located with aninsulating material. After the insulating barrier 880 is formed, asurface of the plating electrode layer 870 may be planarized byperforming chemical mechanical polishing (CMP) or the like. Next, thesubstrate 802, which is a base on which crystal growth occurs, isremoved by performing laser lift-off or the like. The area of the firstseed layer 851 may be larger than that of the first electrode layer 830,and the area of the second seed layer 852 may be larger than that of thesecond electrode layer 840.

Since the plating electrode layer 870 is formed by using plating asdescribed above, an electrode substrate does not need to be prepared andthe semiconductor structure 810 does not need to be bonded to theelectrode substrate. Accordingly, the method of manufacturing thesemiconductor light-emitting device according to the present embodimentmay reduce manufacturing costs and easily achieve mass production andlarge scale fabrication. Also, since the plating electrode layer 870 isformed on one surface of the semiconductor structure 810, packaging maybe possible at a chip level through a flip-chip process. Furthermore,since the plating electrode layer 870 is formed of a metal having highthermal conductivity, a light-emitting device chip having high heatdissipation effect, ensuring long operation, and providing highreliability and high output may be realized.

Also, if an electrode structure is formed on one surface in aconventional semiconductor light-emitting device, since an electrodesubstrate is attached to the semiconductor structure 810, the risk ofmisalignment is high when the electrode substrate is attached to thesemiconductor structure 810 due to the bowing of a wafer. However, sincean electrode substrate does not need to be attached, the semiconductorlight-emitting device according to the present embodiment does not causemisalignment or the like.

FIG. 11 is a cross-sectional view illustrating a semiconductorlight-emitting device 900 according to another embodiment of the presentinvention.

Referring to FIG. 11, the semiconductor light-emitting device 900includes the semiconductor structure 810, and an electrode structuredisposed on one surface 810 b of the semiconductor structure 810.

The semiconductor structure 810 includes the first semiconductor layer811, the active layer 812, and the second semiconductor layer 813 formedby using crystal growth on the substrate 802 (see FIG. 12A). Thesubstrate 802, which is a base on which crystal growth occurs, may beremoved as will be described later.

The electrode structure includes the first electrode layer 830 and thesecond electrode layer 840 disposed on the second semiconductor layer813, and a plating electrode layer 970 electrically connected to thefirst electrode layer 830 and the second electrode layer 840.

The first electrode layer 830 is electrically connected to the firstsemiconductor layer 811 through the contact hole 810 a formed in thefirst semiconductor layer 811 from the second semiconductor layer 813.The contact hole 810 a may be formed by using etching into a mesastructure or a vertical structure. A plurality of the contact holes 810a may be formed. Current spreading may be improved by forming theplurality of first electrode layers 830.

The second electrode layer 840 is disposed on the second semiconductorlayer 813 to be electrically connected to the second semiconductor layer813. The second electrode layer 840 may be disposed on a portion wherethe contact hole 810 a of the second semiconductor layer 813 is notformed.

The insulating layer 820 is coated on a portion of a top surface of thesemiconductor structure 810 other than a portion where the firstelectrode layer 8360 is located and a portion where the second electrodelayer 840 is located. The first electrode layer 830 is insulated fromthe active layer 812, the second semiconductor layer 813, and the secondelectrode layer 840 due to the insulating layer 820.

A first metal layer 951 and a second metal layer 952 respectivelyconnected to the first electrode layer 830 and the second electrodelayer 840 are formed on the insulating layer 820. The first metal layer951 to be connected to the plurality of first electrode layers 930 has alarge area, whereas the second metal layer 952 is formed only on apredetermined portion. Although an area of the first metal layer 951 mayvary according to a size of the light-emitting device 900, it ispreferable that a size of the first metal layer 951 is equal to orgreater than 3 times an area of the second metal layer 952. A thirdmetal layer 953 and a fourth metal layer 954 are formed to be connectedto the first metal layer 951 and the second metal layer 952. The thirdmetal layer 953 is formed to have an area smaller than that of the firstmetal layer 951, and the fourth metal layer 954 is formed to have anarea similar to that of the second metal layer 952.

An insulating layer 956 is filled in a gap between the first metal layer951 and the second metal layer 952 and a gap between the third metallayer 953 and the fourth metal layer 954, to insulate the first metallayer 951 and the second metal layer 952 and to insulate the third metallayer 953 and the fourth metal layer 954.

An insulating barrier 980 is formed on the insulating layer 956. A firstseed layer 961 and a second seed layer 962 respectively connected to thethird metal layer 953 and the fourth metal layer 954 are formed on bothsides of the insulating barrier 980. A first electrode pad 971 and asecond electrode pad 972 are respectively formed on the first seed layer961 and the second seed layer 962. The first electrode pad 971 and thesecond electrode pad 972 may be formed by using plating. Each of thefirst electrode pad 971 and the second electrode pad 972 may have athickness ranging from 15 to 500 μm, and may be formed of a materialincluding at least one selected from the group consisting of Al, Ti, Pt,Ag, Ni, TiN, Au, Sn, and a mixture thereof. If a thickness of each ofthe first electrode pad 971 and the second electrode pad 972 is lessthan 15 μm, each of the first electrode pad 971 and the second electrodepad 972 may not act as a support substrate, and if a thickness isgreater than 500 μm, it may taken a long time to perform plating andcosts may be increased. A width of the insulating barrier 980 (that is,an interval between the first electrode pad 971 and the second electrodepad 972) may preferably range from 1 to 500 μm. If a width of theinsulating barrier 980 is equal to or less than 1 μm, it may bedifficult to perform an insulating process between the electrodes 971and 972. If a width of the insulating barrier 980 is equal to or greaterthan 500 μm, sizes of the electrode pads 971 and 972 may be relativelyreduced, heat generated in the light-emitting device 900 may not beeffectively removed, a temperature of the light-emitting device 900 maybe increased, and thus performance, e.g., luminance, of thelight-emitting device 900 may be reduced.

Since a metal layer and an insulating layer are formed between the firstelectrode layer 830 and the second electrode layer 840, and between thefirst seed layer 961 and the second seed layer 962, an area of thesecond electrode pad 972 may be increased, and thus the semiconductorlight-emitting device 900 may easily change positions and areas of thefirst and second electrode pads 971 and 972 for the purpose ofconnection with a substrate including a contact.

A method of manufacturing a semiconductor light-emitting deviceaccording to another embodiment of the present invention will beexplained.

FIGS. 12A through 12G are cross-sectional views for explaining a methodof manufacturing a semiconductor light-emitting device, according toanother embodiment of the present invention. FIGS. 13A through 13C areplan views illustrating electrode patterns in a process of manufacturinga semiconductor light-emitting device, according to another embodimentof the present invention.

FIG. 12A illustrates a process subsequent to processes of FIGS. 9Athrough 9F, and a detailed explanation of the processes of FIGS. 9Athrough 9F will not be given.

Referring to FIG. 12A, a metal layer (not shown) is formed on the firstelectrode layer 830 and the second electrode layer 840, and the firstmetal layer 951 and the second metal layer 952 respectively connected tothe first electrode layer 830 and the second electrode layer 840 areformed by patterning the metal layer. Referring to FIG. 13A, the firstmetal layer 951 to be connected to the plurality of first electrodelayers 830 has a large area, whereas the second metal layer 952 isformed only on a predetermined portion. The first metal layer 951 andthe second metal layer 952 may be formed along with the metal materials835 and 845 in the process of FIG. 9F which is a previous process.

Referring to FIG. 12B, the insulating layer 956 is formed on theinsulating layer 820 to cover the first metal layer 951 and the secondmetal layer 952. Next, portions of the first metal layer 951 and thesecond metal layer 952 are exposed by patterning the insulating layer956, and then the third metal layer 953 and the fourth metal layer 954are formed on the exposed portions to be connected to the first metallayer 951 and the second metal layer 952, respectively. Referring toFIGS. 13A and 13B, the third metal layer 953 is formed to have an arealess than that of the first metal layer 951, and the fourth metal layer954 is formed to have an area that is 0.5 to 3 times an area of thesecond metal layer 952.

Referring to FIG. 12C, a seed layer 960 for plating is formed on theinsulating layer 956 to cover the third metal layer 953 and the fourthmetal layer 954. Next, a photoresist 964 is formed on the seed layer 960to divide the seed layer 960 into first and second portions A1 and A2.Referring to FIG. 13C, the first portion A1 and the second portion A2respectively contact the third metal layer 953 and the fourth metallayer 954. The second portion A2 has an area that is 1 to 5 times anarea of the fourth metal layer 954.

Referring to FIG. 12D, a first electrode pad 971 and a second electrodepad 972 are respectively formed by performing plating on the firstportion A1 and the second portion A2 with the photoresist 964therebetween. Each of the first electrode pad 971 and the secondelectrode pad 972 may be formed of a metal such as copper, nickel, orchromium, to a thickness of 15 to 500 μm.

Referring to FIG. 12E, a gap 970 a is formed between the first electrodepad 971 and the second electrode pad 972 by removing the photoresist964. A width of the gap 970 a (that is, an interval between the firstelectrode pad 971 and the second electrode pad 972) preferably rangesfrom about 1 to 500 μm. If a width of the gap 970 a is equal to or lessthan 1 μm, it may be difficult to perform insulating between the firstand second electrode pads 971 and 972. If a width of the gap 970 a isequal to or greater than 500 μm, an area of each of the first and secondelectrode pads 971 and 972 may be relatively reduced, heat generated inthe light-emitting devices may not be effectively emitted, a temperatureof the light-emitting device may be increased, and thus performance,e.g., luminance, of the light-emitting device may be reduced.

Referring to FIG. 12F, the seed layer 960 exposed by the gap 970 a isdivided into the first seed layer 961 and the second seed layer 962 byetching the seed layer 960. Next, an insulating barrier 980 is formed byfilling an etched region between the first seed layer 961 and the secondseed layer 962 and the gap 970 a. After the insulating barrier 980 isformed, surfaces of the first electrode pad 971 and the second electrodepad 972 may be planarized by using CMP or the like.

Referring to FIG. 12G, the substrate 802, which is a base on whichcrystal growth occurs, is removed by using laser lift-off or the like.

According to the present embodiment, since an electrode pad may beformed by using plating and an electrode pad forming area may be easilydesigned as described above, a light-emitting device may be easilyinstalled on a substrate in which another contact is formed.

As described above, according to the one or more of the aboveembodiments of the present invention, since a semiconductorlight-emitting device and a method of manufacturing the same supplycurrent to an n-type semiconductor and a p-type semiconductor from abottom surface of a light-emitting structure, light extractionefficiency may be improved. Since direct die bonding may be performedwithout wire bonding, reliability of the semiconductor light-emittingdevice may be improved.

Also, since an area connected to a second electrode layer is increased,electrical connection to a separate substrate in which a contact isformed may be facilitated.

Also, since a thick metal layer formed by using plating is used as asupport substrate, mass production and large area fabrication may beeasily achieved and manufacturing costs may be reduced.

While the present invention has been particularly shown and describedwith reference to exemplary embodiments thereof using specific terms,the embodiments and terms have been used to explain the presentinvention and should not be construed as limiting the scope of thepresent invention defined by the claims. The preferred embodimentsshould be considered in a descriptive sense only and not for purposes oflimitation. Therefore, the scope of the invention is defined not by thedetailed description of the invention but by the appended claims, andall differences within the scope will be construed as being included inthe present invention.

1. (canceled)
 2. A semiconductor light emitting device comprising: asubstrate; a first semiconductor layer disposed on the substrate; anactive layer disposed on the first semiconductor layer; a secondsemiconductor layer disposed on the active layer; a plurality of contactholes extending from the first semiconductor layer to the secondsemiconductor layer, a side surface of each of the plurality of contactholes being inclined with respect to a first direction that isperpendicular to a first top surface of the second semiconductor layer,the plurality of contact holes including a first contact hole; a firstelectrode layer disposed in the first contact hole and disposed on theside surface of the first contact hole, the first electrode layer beingelectrically connected to the first semiconductor layer; a secondelectrode layer disposed on the second semiconductor layer andelectrically connected to the second semiconductor layer; an insulatinglayer disposed on the first top surface of the second semiconductorlayer and disposed in the plurality of contact holes, the insulatinglayer insulating the first electrode layer from the second electrodelayer; a first electrode pad electrically connected to the firstelectrode layer; and a second electrode pad electrically connected tothe second electrode layer, wherein a gap is formed between the firstelectrode pad and the second electrode pad, and a width of the gapranges from 1 μm to 500 μm.
 3. The semiconductor light emitting deviceof claim 2, wherein the insulating layer is disposed on a second topsurface of the second electrode layer.
 4. The semiconductor lightemitting device of claim 2, wherein the insulating layer insulates thefirst electrode layer from the active layer and from the secondsemiconductor layer.
 5. The semiconductor light emitting device of claim2, wherein the side surface of the first contact hole is inclined withstep.
 6. The semiconductor light emitting device of claim 2, furthercomprising an insulating barrier disposed between the first electrodepad and the second electrode pad.
 7. The semiconductor light emittingdevice of claim 2, wherein a size of each of the plurality of contactholes ranges from 5 to 300 μm.
 8. The semiconductor light emittingdevice of claim 2, wherein the second electrode layer is a reflectivelayer.
 9. The semiconductor light emitting device of claim 2, furthercomprising a reflective material partially or entirely coated on theside surface that is inclined.
 10. A semiconductor light emitting devicecomprising: a substrate; a first semiconductor layer disposed on thesubstrate; an active layer disposed on the first semiconductor layer; asecond semiconductor layer disposed on the active layer; a firstelectrode layer electrically connected to the first semiconductor layer;a second electrode layer disposed on the second semiconductor layer andelectrically connected to the second semiconductor layer; a firstinsulating layer disposed on a first top surface of the secondsemiconductor layer, and insulating the first electrode layer from thesecond electrode layer; a second insulating layer disposed on the firstinsulating layer and contacting the first insulating layer; a firstmetal layer connected to the first electrode layer; a second metal layerconnected to the second electrode layer; a first electrode padelectrically connected to the first electrode layer; and a secondelectrode pad electrically connected to the second electrode layer,wherein a gap is formed between the first electrode pad and the secondelectrode pad, a width of the gap ranges from 1 μm to 500 μm, and thesecond insulating layer insulates the first metal layer from the secondmetal layer.
 11. The semiconductor light emitting device of claim 10,further comprising a plurality of contact holes extending from the firstsemiconductor layer to the second semiconductor layer.
 12. Thesemiconductor light emitting device of claim 11, wherein the firstelectrode layer is disposed in at least one of the plurality of contactholes.
 13. The semiconductor light emitting device of claim 12, whereina size of each of the plurality of contact holes ranges from 5 to 300μm.
 14. The semiconductor light emitting device of claim 10, wherein thesecond electrode layer is a reflective layer.
 15. A semiconductor lightemitting device comprising: a substrate; a first semiconductor layerdisposed on the substrate; an active layer disposed on the firstsemiconductor layer; a second semiconductor layer disposed on the activelayer; a first electrode layer electrically connected to the firstsemiconductor layer; a second electrode layer disposed on the secondsemiconductor layer and electrically connected to the secondsemiconductor layer; an insulating layer disposed on a first top surfaceof the second semiconductor layer, and insulating the first electrodelayer from the second electrode layer; a first electrode padelectrically connected to the first electrode layer; and a secondelectrode pad electrically connected to the second electrode layer,wherein a gap is formed between the first electrode pad and the secondelectrode pad, a width of the gap ranges from 1 μm to 500 μm, and aportion of the first electrode pad is disposed directly above the secondelectrode layer.
 16. The semiconductor light emitting device of claim15, wherein each of the first electrode pad and the second electrode padis formed with a thickness of 5 μm to 500 μm.
 17. The semiconductorlight emitting device of claim 15, wherein each of the first electrodepad and the second electrode pad is formed of a metal selected from agroup consisting of copper, nickel and chromium.
 18. The semiconductorlight emitting device of claim 15, further comprising a plurality ofcontact holes extending from the first semiconductor layer to the secondsemiconductor layer, wherein the first electrode layer is disposed on atleast one of the plurality of contact holes.
 19. The semiconductor lightemitting device of claim 16, wherein a size of each of the plurality ofcontact holes ranges from 5 to 300 μm.
 20. The semiconductor lightemitting device of claim 15, wherein the insulating layer is disposed ona second top surface of the second electrode layer.
 21. Thesemiconductor light emitting device of claim 15, wherein the secondelectrode layer is a reflective layer.